portainer/api/kubernetes/kubeconfig_service.go

105 lines
4.0 KiB
Go

package kubernetes
import (
"crypto/x509"
"encoding/base64"
"encoding/pem"
"fmt"
"io/ioutil"
"log"
"github.com/pkg/errors"
portainer "github.com/portainer/portainer/api"
)
// KubeConfigService represents a service that is responsible for handling kubeconfig operations
type KubeConfigService interface {
IsSecure() bool
GetKubeConfigInternal(endpointId portainer.EndpointID, authToken string) kubernetesClusterAccess
}
// KubernetesClusterAccess represents core details which can be used to generate KubeConfig file/data
type kubernetesClusterAccess struct {
ClusterServerURL string `example:"https://mycompany.k8s.com"`
CertificateAuthorityFile string `example:"/data/tls/localhost.crt"`
CertificateAuthorityData string `example:"MIIC5TCCAc2gAwIBAgIJAJ+...+xuhOaFXwQ=="`
AuthToken string `example:"ey..."`
}
type kubeConfigCAService struct {
httpsBindAddr string
certificateAuthorityFile string
certificateAuthorityData string
}
var (
errTLSCertNotProvided = errors.New("tls cert path not provided")
errTLSCertFileMissing = errors.New("missing tls cert file")
errTLSCertIncorrectType = errors.New("incorrect tls cert type")
errTLSCertValidation = errors.New("failed to parse tls certificate")
)
// NewKubeConfigCAService encapsulates generation of core KubeConfig data
func NewKubeConfigCAService(httpsBindAddr string, tlsCertPath string) KubeConfigService {
certificateAuthorityData, err := getCertificateAuthorityData(tlsCertPath)
if err != nil {
log.Printf("[DEBUG] [internal,kubeconfig] [message: %s, generated KubeConfig will be insecure]", err.Error())
}
return &kubeConfigCAService{
httpsBindAddr: httpsBindAddr,
certificateAuthorityFile: tlsCertPath,
certificateAuthorityData: certificateAuthorityData,
}
}
// getCertificateAuthorityData reads tls certificate from supplied path and verifies the tls certificate
// then returns content (string) of the certificate within `-----BEGIN CERTIFICATE-----` and `-----END CERTIFICATE-----`
func getCertificateAuthorityData(tlsCertPath string) (string, error) {
if tlsCertPath == "" {
return "", errTLSCertNotProvided
}
data, err := ioutil.ReadFile(tlsCertPath)
if err != nil {
return "", errors.Wrap(errTLSCertFileMissing, err.Error())
}
block, _ := pem.Decode(data)
if block == nil || block.Type != "CERTIFICATE" {
return "", errTLSCertIncorrectType
}
certificate, err := x509.ParseCertificate(block.Bytes)
if err != nil {
return "", errors.Wrap(errTLSCertValidation, err.Error())
}
return base64.StdEncoding.EncodeToString(certificate.Raw), nil
}
// IsSecure specifies whether generated KubeConfig structs from the service will not have `insecure-skip-tls-verify: true`
// this is based on the fact that we can successfully extract `certificateAuthorityData` from
// certificate file at `tlsCertPath`. If we can successfully extract `certificateAuthorityData`,
// then this will be used as `certificate-authority-data` attribute in a generated KubeConfig.
func (kccas *kubeConfigCAService) IsSecure() bool {
return kccas.certificateAuthorityData != ""
}
// GetKubeConfigInternal returns K8s cluster access details for the specified environment(endpoint).
// On startup, portainer generates a certificate against localhost at specified `httpsBindAddr` port, hence
// the kubeconfig generated should only be utilised by internal portainer binaries as the `ClusterServerURL`
// points to the internally accessible `https` based `localhost` address.
// The struct can be used to:
// - generate a kubeconfig file
// - pass down params to binaries
func (kccas *kubeConfigCAService) GetKubeConfigInternal(endpointId portainer.EndpointID, authToken string) kubernetesClusterAccess {
clusterServerUrl := fmt.Sprintf("https://localhost%s/api/endpoints/%s/kubernetes", kccas.httpsBindAddr, fmt.Sprint(endpointId))
return kubernetesClusterAccess{
ClusterServerURL: clusterServerUrl,
CertificateAuthorityFile: kccas.certificateAuthorityFile,
CertificateAuthorityData: kccas.certificateAuthorityData,
AuthToken: authToken,
}
}